The airline Air China has been using Boeing 777-300ER long-haul aircraft between Shanghai and Frankfurt am Main since last week. These have 311 seats.
So far, mostly Airbus A350-900s have been used on this route. Available flight schedule data shows that Air China intends to fly Boeing 2023-777ERs at least once a week in the 300 summer flight schedule as well. This machine type is to come from Shanghai to Frankfurt am Main on the Tuesday traffic day.